Southern blot analysis of genomic DNA was performed after digestion with 14 restiction endonucleases in four Japanese families affected with total kininogen deficiency and one Japanese family with isolated high molecular weight kinioogen deficiency, as well as in 15 normal subjects. The blots were hybridized with a kininogen cDNA probe (phKG36). In cases of total kininogen deficiency, the kininogen gene appeared to be grossly normal at the level of whole genome Southern blotting, suggesting that there were no major deletions, insertions or rearrangement in the kininogen gene. In a case of isolated high molecular weight kininogen deficiency, a partial deletion in intron 7 was identified. This deletion might have some influence on the mechanism of alternative splicing. Restriction fragment length polymorphism was detected with Msp I, but carrier detection in these deficient families was impossible.
alternative splicing RFLP (restriction fragment length polymorphism)